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Straddling diverse worlds

Dr Adrian Tiplady’s “diverse skills set” have been credited by Professor Justin Jonas, head scientist of the local Square Kilometre Array Project (SKA) and Professor of Physics and Electronics at Rhodes University, as key to South Africa’s bid.

Dr Tiplady prepared the local scientific proposal - which ran over 27 000 pages - for consideration by the world’s foremost international experts in the field, while also having to negotiate with everyone from farmers to cellular phone executives to help boost South Africa’s bid.

Fortunately Dr Tiplady has never had a problem straddling diverse worlds. A gifted saxophonist and aspiring orchestra conductor, the Durbanite came to Rhodes University in 1997 to study music. But he also had an interest in electronics, particularly for “building stuff”, and astronomy.

He received a Bachelor degree in Physics and Electronics, Computer Science, Musicology and Compositional Techniques (with distinction). “I also - sort of illegally (it wasn’t technically allowed in combination with his other courses) - majored in the practical performance side.”

He went on to receive an Honours degree in Telecommunications and did his PhD in Physics and Electronics, specialising in Radio Astronomy. His thesis involved the development of instruments, while he also modelled the precession of radio pulsars as part of his dissertation.

Dr Tiplady largely credits his own development in the field to the personal attention he received at Rhodes, South Africa’s smallest university, where there is one-on-one teaching, particularly in Physics and Electronics. “It was a completely different learning experience than being at one of the large universities, where you are one of a sea of students, fighting for laboratory time.”

Still - the music beckoned and during the completion of his thesis towards the end of 2004, he was considering moving to Paris to become a jazz musician. Then he received a call from Prof Jonas, his doctoral supervisor, asking whether he wanted to get involved in SA’s SKA bid. He immediately responded to the challenge, initially taking on the role of developing equipment at the Hartebeesthoek

Radio Astronomy Observatory for the highly sensitive radio frequency measurements to be conducted in the Karoo. From here he quickly became involved in compiling the original submission to host the SKA in 2005, for which South Africa was shortlisted in 2006.

It was during this time that the local SKA team decided that in addition to hosting the SKA, South Africa needed to demonstrate its technical capability. This led to the establishment of the Karoo Array Telescope (KAT-7), and Dr Tiplady got increasingly involved, including making sure that the environment around the SKA bid site, 90 km outside of Carnarvon in the Northern Cape, is radio quiet.

Radio telescopes are extremely sensitive instruments - the SKA telescope will be able to pick up radar fifty light years away. This can be seriously impeded by cellphone and televisions signals, as well as the electromagnetic interference generated from electrical devices such as cars. (The telescope can be affected by a car 11 km away.)

Dr Tiplady is one of the driving forces in establishing - through the Astronomy Geographic Advantage Act, declared in 2007 - the protected area commonly known as the Karoo Radio Astronomy Reserve, which is uniquely protected from activities detrimental to radio astronomy.

Apart from getting government on board, Dr Tiplady also had to consult with and educate everyone from broadcasters and cellphone groups to farmers and representatives of the local population - some 35 000 people - to limit the spread of particularly telecommunication signals. “It was important to get the buy-in from all stakeholders,” says Dr Tiplady.

Another threat for the SKA bid was the energy giant Shell’s plans for hydraulic fracturing (fracking) in the Karoo. This technology extracts natural gas trapped in the rock several kilometres beneath the earth’s surface through the injection of water, sand and chemicals at extremely high pressures. The electromagnetic interference from the heavy machinery used for the process has the potential to interfere with the SKA telescopes if not properly coordinated, explains Dr Tiplady, who now serves on the Working Group of the South African Inter Ministerial Task Team on Shale Gas and Hydraulic Fracturing.

Apart from establishing the protected area around the site, Dr Tiplady’s main responsibility was putting together the bid documentation. The final proposal was submitted last year. The document detailed the atmospheric, geotechnical and meteorological characteristics of the site, including information about aspects like humidity, wind and radio frequencies. Specifics about planned and existing infrastructure, the design of electricity supplies, all buildings, civil engineering works and data connectivity plans had to be set out in the document, along with the total costing.

Since South Africa’s bid also involves eight other African countries, Dr Tiplady had to include substantial information about transport costs and logistics as well as cross border regulations and customs and excise duties. It has been seven gruelling years, and at times Dr

Tiplady must have longed for the life of a saxophonist in the Latin Quarter. But that would have come at a huge cost to South Africa, who is indebted to him for putting together the country’s winning SKA bid.

Caption: Dr Adrian Tiplady - SKA Site Bid Manager